If you have at least FTP access you can get the site up and running again by removing the translatepress-multilingual folder in wp-content/plugins. Then you can reinstall the plugin once the author has fixed the repository.
One of my clients had this same problem. The failing call to v4.mastersliders.com caused a variable to be empty, which caused a syntax error in a javascript file.
I fixed it temporarly by changing line 161 in admin/includes/classes/class-msp-admin-assets.php to the following:
wp_add_inline_script( $this->panel_js_handler, ‘var __MSP_DATA = ‘.($msp_data != “”? $msp_data : ‘””‘).’;’ );
